1. Field of the Invention
The present invention relates to a system and a method for power management, directed to an image forming apparatus, and a usage management apparatus of the image forming apparatus, particularly to a technique of managing a power supply in cooperation with an entry control apparatus for controlling user's access to a particular area.
2. Description of the Related Art
Recently, efforts to reduce power consumption are made for many electric products as concern for environmental issues is being grown. The efforts also involve business machines typified by copying machines. For example, Japanese Laid-Open Patent Publication No 2004-038381 discloses a power supply apparatus including means for detecting a state of use of a main information processing apparatus among a plurality of information processing apparatuses connected to a power supply apparatus, and means for supplying alternating current power to the information processing apparatuses connected to the power supply apparatus in the case where the main information processing apparatus is in the use state while stopping supply of the alternating current power to the information processing apparatuses connected to the power supply apparatus in the case where the main information processing apparatus is in the nonuse state.
With the recent development in the information communication technology, an entry control system in which an IC (Integrated Circuit) card or the like is used has become popular. There has been proposed a technique of utilizing such an entry control system to reduce the power consumption of the business machines. For example, Japanese Laid-Open Patent Publication No. 10-208173 discloses an entry control system including display means for displaying a warning in a caretaker's room when a value exceeding a predetermined electricity usage amount is detected while a tenant is absent in a room.
Sometimes only a particular user is permitted to use business machines such as an image forming apparatus depending on scope of business in an office. For example, in a usage manner, only a user who is given a certain responsibility is permitted to use the image forming apparatus. In such usage manner, after the user permitted to use the image forming apparatus goes home, the image forming apparatus is not used even if other users exist in the office. Therefore, in such a situation, it is preferable to set the image forming apparatus in a standby mode or to turn off the image forming apparatus.
However, in Japanese Laid-Open Patent Publication No. 10-208173, only the electricity usage amount is managed in the case where all the tenants leave the rooms, and the electricity usage amount is not managed for each business machine.